Problem with buttons

[FW200]

hi,

I have been using O2 for a while(since it came out) but suddenly my buttons are black..
http://members.home.nl/famvreuls/buttons.JPG
This way i cant work offcourse so my Question is if anyone knows how i can get rid of this problem?? http://www.flashpoint1985.com/ikonboard301/iB_html/non-cgi/emoticons/sad.gif

Thanks,

FW200